<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            font-size: 50px;
        }
        .grid-con{
            margin: 0;
            padding: 10px;
            width: 500px;
            background-color: blue;
            display: grid;
            grid-template-columns: repeat(4,auto);
            grid-template-rows: 100px 200px 100px 100px;
            /* grid-template-columns: 1fr 1fr 1fr; */
            column-gap: 10px;
            row-gap: 20px;
            grid-auto-flow: row dense;

        }
        .grid-con>div{
            background-color: blueviolet;
        }
       
        .item1{
            grid-row-start: 1;
            grid-row-end: 4;
        }
        .item2{
            grid-column-start: 2;
            grid-column-end: 4;
        }
        .item3{
            grid-column-start: 2;
            grid-column-end: 4;
        }
    </style>
</head>
<body>
    <div class="grid-con">
        <div class="item1">1</div>
        <div class="item2">2</div>
        <div class="item3">3</div>
        <div class="item4">4</div>
        <div class="item">5</div>
        <div class="item">6</div>
        <div class="item">7</div>
        <div class="item">8</div>
        <div class="item">9</div>
        <div class="item">10</div>
        <div class="item">11</div>
        <div class="item">12</div>
    </div>
</body>
</html>